Crimping tool

ABSTRACT

A tool for crimping tubular or sleevelike connectors onto electrical conductors and comprising relatively fixed die means adapted to operatively support a connector during a crimping operation, first and second relatively movable die means adapted to independently cooperate with the fixed die means to crimp a connector therebetween, explosive means for moving the relatively movable die means from deactuated to actuated positions, means for detonating the explosive means, and means for biasing the relatively movable die means toward their respective deactuated positions.

United States Patent Inventor Robert K. Fielder Fiagler Beach, Fla.Appl. No. 794,155 Filed Jan. 27, 1969 Patented Aug. 17, 1971 AssigneeEarl L. Halladay a part interest CRIMPHQG TOOL 10 Claims, 5 DrawingFigs.

US. Cl 29/203 D, 29/254, 72/430 int. Cl ..l-l01r 43/05 823p 19/04, B21i15/24 Field of Search 29/254, 203

DT, 203, 203 D; 72/430 [56] References Cited UNITED STATES PATENTS2,968,043 1/1961 Demler 72/430 3,062,260 11/1962 Temple etal.... 72/430X3,163,200 12/1964 Broske et a1. 29/254 X 3,434,511 3/1969 Mixon, Jr.29/203 X Primary ExaminerThomas H. Eager Attorney-Harness, Dickey &Pierce PATENIEU AUG] 7 ran SHEET 1 [IF 2 n u c i .W 2 f X f fly mv Q wv44% m \wn wm N T L m in i mm wk o on CRIMPING TOOL BACKGROUND OF THEINVENTION It has heretofore been proposed to secure tubular orsleevelike connectors fabricated, for example, of aluminum or a similarelectrically conductive material, onto electrical conductors or wires bymeans of crimping dies which are actuated by an explosive force. Typicalexamples of heretofore known and used devices are shown in US. Pat. No.2,968,043, for Hand Tool For Crimping Electrical Conductors, and No.3,062,260 for Explosively Actuated Press. Although such prior artcrimping devices have been found to operate satisfactorily when crimpingtwo wires of substantially the same diameter or gage, the effectivenessof such devices has been doubtful when they have been used to connectwires of different sizes, due primarily to the fact that a commoncrimping die was used to crimp a connector sleeve into operativeengagement with each of the different size wires. Such heretofore knownand used crimping devices have also been objectionable from thestandpoint that they were frequently of a relatively complicated andbulky construction, thereby preventing convenient manipulation,actuation and storage thereof.

Generally speaking, the present invention is directed toward a new andimproved crimping tool which overcomes the above undesirable features ofsimilar-type tools known in the prior art. More particularly, thecrimping tool of the present invention is characterized by the provisionof a. pair of independently movable crimping devices that are actuablein response to an explosive force to move toward and into engagementwith the electrical connector to be crimped. .By virtue of the fact thatthe aforesaid dies are independently movable, each end of the connectoris compressed to the limit of the force applied, regardless of the forceapplied to the opposite end thereof. Accordingly, a positive andeffective electrical connection is achieved between each end of theconnector and the associated electrical conductor, even though the twoconductors may be of different sizes. The crimping tool of the presentinvention is further characterized by an extremely simple design whichrenders itself to economical manufacture, convenient assembly and aminimum amount of maintenance, with the result that the tool isdesirable not only from the standpoint of being effective in operation,but also by having a long and durable operational life and beingeconomical to commercially produce.

SUMMARY OF THE INVENTION This invention relates generally to crimpingtools and more particularly, to a new and improved crimping tool of thetype adapted to crimp tubular or sleevelike metallic connectors toelectrical conductors.

Accordingly, it is a general object of the present invention to providea new and improved crimping tool.

It is another object of the present invention to provide a crimping toolof the above-described type that is lightweight and compact in size soas to permit use thereof in relatively confined areas.

It is a more particular object of the present invention to provide acrimping tool of the above-described type which utilizes a blankexplosive cartridge as a source of power, thereby eliminating the use ofphysical strength, long and bulky handles and/or hydraulic or electricalactuating mechanisms.

It is another object of the present invention to provide a crimping toolwhich is extremely fast acting so as,to produce a cold welding effectbetween the electrical conductors and the connectors being crimpedthereto, with the result that an effective electrical connection isprovided therebetween.

It is still another object of the present invention to provide acrimping tool which utilizes a pair of independently movable pistonswhich provide for effective crimping of the associated connector towires of different diameters.

It is a further object of the present invention to provide a crimpingtool of the above-described type wherein the crimping device functionsto confine the explosive actuating means so as to assure completeignition thereof.

It is another object of the present invention to provide a new andimproved crimping tool which utilizes a novel spring clip arrangementfor positively securing the electrical conductors to. the tool during acrimping operation so as to prevent inadvertent movement of the wiresrelative to the tool.

It is still another object of the present invention to provide acrimping tool of an object extremely simple design, and which istherefore economical to manufacture and easy to assemble.

Other objects and advantages of the present invention will becomeapparent from the following detailed description, taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a longitudinalcross-sectional view of a crimping tool in accordance with a preferredembodiment of the present invention;

FIG. 2 is a cross-sectional view of the crimping tool illustrated inFIG. 1, as taken substantially along the line 2-2 of FIG. 1;

FIG. 3 is an end elevational view of the crimping tool shown in FIGS. 1and 2 FIG. 4 is a side elevational view of a modified form of the springclip means utilized to secure electrical conductors to the crimping toolduring a crimping operation, and

FIG. 5 is an exploded perspective view of an electrical connector and apair of conductors which may be secured together via the connector uponoperation of the crimping tool of the present invention.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT For purposes of clarity,the terms inwardly, outwardly" and derivatives thereof will havereference to the geometric center of the crimping tool of the presentinvention and the various component parts thereof. Similarly, the termsforwardly," rearwardly and the like will have reference to the presentinvention and the component parts thereof shown in FIGS. 1 and 2, withthe forward end of the tool being located at the right side of theseFigures.

Referring now in detail to FIG. 1 of the drawings, a crimping tool 10,in accordance with a preferred embodiment of the present invention, isshown as comprising a longitudinally extending annular or tubularhousing 12 which defines a generally cylindrical-shaped cavity 14therewithin. The forward and rearward ends of the housing 12, around theinner periphery thereof, are threaded, as seen at 16 and 18,respectively, and the housing 12 is formed with a series of radiallyoutwardly extending vent apertures, generally designated 20, around anintermediate portion thereof. An annular shroud or shield member 22extends around the outer periphery of the housing 12 at a positionlongitudinally aligned with the apertures 20. As illustrated, the shield22 comprises a mounting section 24, which may be secured by any suitablemeans around the periphery of the housing 12, and a longitudinallyextending sleeve section 25 that is spaced radially outwardly from theperiphery of the housing 12 and defines an annular passageway 26therewith which communicates with the apertures 20, for reasons later tobe described.

The rearward end of the housing 12 is provided with a breechblock 28which comprises an annular, externally threaded section 30 adapted to bethreadably mounted within the threaded portion 16 of the housing 12. Thebreechblock 28 also comprises a rearwardly extending, reduced-diameter,externally threaded support section 32 that is arranged coaxially of thesection 30 and defines a longitudinally extending bore 34 therewith. Therearward end of the bore 34 is counterbored, as seen at 36, and isadapted to have a suitable explosive cartridge 38 such as, for example,a 0.22 caliber rimfire blank cartridge or the like, disposed therein,with the cartridge rim being received within the counterbore 36, asillustrated.

The support section 32 of the breechblock 28 is adapted to function inoperatively supporting an elongated receiver member 40 upon the tool 10.As best seen in FIG. 1, the receiver 40 comprises an annular collarsection 42 that is in ternally threaded and is adapted to be threadablymounted upon the support section 32 of the breechblock 28. The receiver40 also comprises a rearwardly extending firing pin support section 44that defines a longitudinally extending cylindrical bore 46 therewithin.The forward end of the bore 46 is communicable with the rearward end ofthe counterbore 36 by means of a longitudinally extending slot 48 formedin the receiver 40 intermediate the sections 42, 44 thereof. Disposedwithin the bore 46 is a reciprocable firing pin, generally designated50, that comprises an annular guide section 52 which is designed to beslidably received within the bore 46. Extending forwardly from the guidesection 52 and integrally connected thereto is a cartridge engaging pinsection 54 which is adapted to slide longitudinally within the slot 48and engage the rim of the cartridge 38 located in the breechblock 28.Extending rearwardly from the guide section 52 of the firing pin 50 is alongitudinally projecting actuating section 56 which projects out therearward end of the receiver 40 and is provided with a manuallyengageable, externally serrated knob 58. An actuating spring 60 extendscircumjacent the firing pin section 56 interjacent the rearward side ofthe guide section 52 and a retaining nut 62 that is threadably mountedwithin the rearward end of the bore 46. Briefly, in operation of thecrimping tool 10, the operator grasps the firing pin 50 by the knob 58thereof and pulls the pin 50 rearwardly against the resistance of thespring 60. Thereafter, the operator will release the knob 58 and thefiring pin will be biased forwardly under the influence of thespring'60, with the result that the section 54 thereof will engage therim of the cartridge 38 to effectuate ignition thereof.

The forward end of the crimping tool of the present invention isprovided with a female die member, generally designated 64, whichcomprises a longitudinally extending section 66 that terminates at itsforward end in an arcuately upwardly extending section 68 defining asemicylindrical recess 70 that extends transversely to the longitudinalaxis to the tool 10. The recess 70 is defined by a radius which is thesame or slightly larger than the radius of the connectors which are tobe crimped upon operation of the tool 10 whereby the connectors may bereceived within the recess 70 in the manner shown in FIG, I. The end ofthe die section 66 opposite the section 68 is integrally connected to anannular mounting section 72 which is externally threaded and is therebyadapted to be threadably mounted within the threaded section 18 of thehousing 12, as illustrated, whereby to secure the die member 64 to thetool 10. The mounting section 72 is formed with a pair of longitudinallyextending, spaced parallel bores 74 which function in a mannerhereinafter to be described.

The crimping tool 10 is provided with a pair of male die members whichare preferably identical in construction and generally designated by thenumeral 76. Each of the die members 76 comprises a generallycylindrically shaped, longitudinally extending section 78 adapted to beslidably received within one of the bores 74. Each of the die members 76also comprises a head section 80 on the forward end thereof, thesections 80 being slightly larger in diameter than the die sections 78and defining laterally aligned arcuate face portions 82 which are ofagenerally complementary shape with respect to the electrical connectorswhich are to be crimped during operation of the tool 10.

As best illustrated in FIG. 2, the rearward ends of the male diesections 78 are operatively connected to a pair of piston members,generally designated 84, which are longitudinally slidably disposedwithin the cavity 14. Means in the form of suitable connecting pins orthe like 86 are preferably utilized in securing the die members 76 tothe piston 84 against relative movement therebetween. By virtue of theabovedescribed construction, longitudinal movement of the piston members84 within the cavity 14 will result in simultaneous movement in the samedirection of the die members 76 toward and away from a connector locatedin the recess 70 of the female die member 64.

The piston members 84 and male die members 76 are adapted to be normallyretained in a deactuated or retracted position, as seen in FIGS. 1 and2, by means of a plurality of return springs, generally designated 8-8,that extend longitudinally within the cavity 14. The rearward ends ofthe springs 88 are received within suitable longitudinally extendingbores 89 formed in the forward ends of the pistons 34, and the for wardends of the springs 88 are mounted circumjacent the rearward ends of aplurality of guide pins 90 fixedly mounted on the rearward side of themounting section 72 of the female die member 64. In operation of thetool 10, the pistons 34 and die members 76 move forwardly against theresistance of the springs 88 to provide the desired crimping action on asuitable connector mounted within the recess '70, and upon completion ofthe crimping operation, the springs 88 function to bias the pistons 84and male die members 76 rearwardly to a position wherein the rearwardsides of the pistons 84 abuttingly engage the forward side of thebreechblock section 30. A particular feature of the above constructionresides in the fact that the rearward sides of the pistons 84 functionto close or confine the forward end of the bore 34 within which thecartridge 38 is operatively mounted. This assures that the cartridge 38will be confined within a relatively small volume upon initial ignitionthereof so as to provide for complete and efficient combustion of thepowder charge contained therein.

Mounted on the opposite sides of the female die member 64 and projectingoutwardly therefrom is a pair of spring clip members, generallydesignated by the numeral 92. Each of the members 92 is of a generallyU-shaped configuration, as seen in FIG. 3, and comprises a pair ofspaced parallel leg sections 94, 96 and an intermediate section 98extending therebetween. The members 92 are fixedly secured to thelaterally outer sides of the female die member 64 by means of aplurality of inwardly projecting mounting screws, generally designated100, which extend through the intermediate sections 98 of the members 92and are received within suitable interiorly threaded bores 102 in thedie member 64. The leg sections 94, 96 of the spring clip members 92 arecut away as best seen at 103 in FIGS. 2 and 3, whereby to define a pairof arcuately inwardly converging conductor-engaging sections 104 betweenwhich suitable wire conductors may be inserted and positively retainedpreparatory to and during a crimping operation. By virtue of the arcuateconfiguration of the sections 104, once a wire conductor has beeninserted therebetween, it will be positively retained in place duringthe crimping operation, thereby assuring against any relative movementof the conductor with respect to the electrical connector during thecrimping operation.

FIG. 4 illustrates an alternate embodiment of the spring clip meansshown in FIGS. 1 through 3 for securing wire conductors to the crimpingtool 10 of the present invention. More particularly, FIG. 4 illustratesa spring clip means, generally designated 108 and comprising a generallylaterally extending support member 110 adapted to be secured to thefemale die member 64 by any suitable means. Extending upwardly from thesupport member 110 is a securing block member 112 which carries aplurality of conductor-engaging fingers 114 that are pivotably mountedat one end, as seen at 116 to the block 112. Fingers 114 are adapted tobe resiliently biased into engagement with the end of a conductor, whichis to be secured during a crimping operation, by means of associatedspring means 118 which act against the fingers 114 through suitableplungers 120, with the spring means 118 being suitably mounted upon thesupport member 110 and an inwardly extending member 122 which is spacedabove the member 110 and connected to the block 112 through suitablescrew means 124. It will be seen that when the end of a conductor isinserted between the inner ends of the fingers 114, the fingers 114 willbe biased apart against the resistance of the spring means 118, and thatthe fingers 114 will be resiliently biased into engagement with theperiphery of the conductor through the spring means 118 and plungers 120so as to resist outward movement of the conductor with respect to thetool during a subsequent crimping operation.

In operation of the crimping tool 10 of the present invention, a typicaltubular or sleevelike connector shown in FIG. 5 and designated by thenumeral 126 is inserted within the recess 70 of the female die member64. Thereafter, the pair of wire conductors, shown in FIG. 5 anddesignated by the numerals 128 and 130, which are to be secured by meansof the connector 126, are inserted through the spring clip members 92and into the opposite ends of the connector 126. The clip members 92will be seen to prevent any lateral movement of the conductors 128, 130relative to the connector 126 during the subsequent crimping operation,as above described. The receiver 40 may be unscrewed from the section 32of the breechblock 28 and a suitable blank cartridge 38 be inserted intothe bore 34. Thereafter, the receiver 40 may be reassembled preparatoryto actuating the tool 10. At such time as it is desired to effect acrimping operation, the firing pin 50 is retracted rearwardly, therebycompressing the spring 60. The firing pin 50 may be released whendesired, with the result that the spring 60 will bias the pin 50forwardly, resulting in the pin section 54 engaging the rim of thecartridge 38 to effect ignition thereof. The explosive gas generated byignition of the cartridge 38 will force the piston members 84 and maledie members 76 carried thereon forwardly, resulting in the face portions82 impinging against the side of the connector 126 opposite the recess70, thereby effecting the desired crimping action which results in theconductors I28, 130 being secured to the connector 126. The aforesaidexplosive gases produced by the cartridge 38 are communicated or ventedthrough the apertures and then forwardly through the passageway 26defined between the housing 12 and shield 22, thereby preventing suchgas from injuring the operator. As the piston members 84 thus moveforwardly, the return springs 88 are compressed, which springs 88therefore cause the pistons 84 and die members 76 to be moved rearwardlyupon completion of the crimping operation. Once the crimping operationhas been completed, the entire assembly consisting of the connector 126and conductors 128 and 130 may be removed from the tool 10 by slidingthe assembly rearwardly so that the con nector 126 clears the recess 70and the conductors 128, 130 are disengaged from the spring clip members92, thereby preparing the tool 10 for a subsequent operational cycle.

A particularly important feature of the crimping tool 10 of the presentinvention will be seen from the fact that the male die members 76 andpistons 84 are free to move independently of one another during acrimping operation. This allows each end of the connector being crimpedto be compressed to the limit of the force required, regardless of theforce applied to the opposite end of the connector. This feature permitsone end of the connector to be crimped a greater amount than the otherend thereof in the event conductors of two different diameters are beingsecured to one another. Such an action is not possible wherein a singledie is used to crimp each end of the connector, and accordingly, thecrimping tool 10 of the present invention assures for positiveelectrical connection between a pair ofconductors and an associatedconnector, r-egardless of whether or not the conductors are of the samesize. Another feature of the present invention will be seen from thesmall, lightweight construction thereof, which permits the tool to beused in confined and difficult locations. By using an explosivecartridge as a source of power, physical strength is minimized to theextreme, as is the need for ancillary mechanical-type tools requiringlong and bulky handles, or alternatively, hydraulic or electricallyenergized power means. The fast action of the tool in effecting a crimpwill have an extremely beneficial cold welding effect between the wiresand the connector, thereby providing for effective electricalconnections. The tool 10 is designed to have sufficient power so thatharder alloy crimping connectors may be used, thereby permitting the useof smaller size connectors, while still providing the strength andcurrent-carrying capacity of much larger connectors heretofore required.

While it will be apparent that the preferred embodiments illustratedherein are well calculated to fulfill the objects above stated, it willbe appreciated that the present invention is susceptible tomodification, variation and change without departing from the properscope or fair meaning of the subjoined claims.

I claim:

1. In an electrical-connector-crimping tool for operatively connectingfirst and second wire elements,

relatively fixed die means adapted to operatively support a connectorduring a crimping operation,

first and second independently movable die means cooperable with saidfixed die means to crimp a connector therebetween,

piston means for applying an explosive force to said mova ble an diemeans, whereby said movable die means will be biased independentlytoward said connector supported on said fixed die means and therebyexert independent compressive forces against said connector to securesaid connector to said first and second wire elements regardless ofwhether or not said elements are of the same cross-sectional size, and

means for detonating an explosive device adjacent said piston means forproducing said force.

2. A tool for crimping electrical connectors as set forth in claim Iwhich includes first and second reciprocable piston means cooperablewith said relatively movable die means.

3. A tool for crimping electrical connectors as set forth in claim lwherein said means for detonating an explosive device comprises firingpin means and spring means for resiliently biasing said firing pin meanstoward said explosive device.

4. A tool for crimping electrical connectors as set forth in claim 1wherein said relatively fixed die means comprises a female memberadapted to operatively support a connector, and wherein said first andsecond relatively movable die means comprises first and second male diesadapted to independently move toward and away from said female die tocrimp a connector therebetween.

5. A tool for crimping electrical connectors as set forth in claim 4which includes first and second spring means for biasing said first andsecond male dies toward deactuated posi trons.

67 A tool for crimping electrical connectors as set forth in claim 1which includes spring clip means for positively securing at least one ofsaid wire elements to which a connector is to be crimped in apreselected position relative to said fixed die means.

7. A tool for crimping electrical connectors as set forth in claim 6wherein said spring clip means comprises a pair of opposed spring clipmembers each having portions adapted to positively engage said one wireelement to which a connector is to be crimped, whereby to resistmovement of the element relative to the tool during a crimpingoperation.

8. A tool for crimping electrical connectors as set forth in claim 6wherein said spring clip means includes wire-engaging finger means andspring means resiliently urging said finger means toward a positionengaging the wire element to which a connector is to be crimped.

9. A tool for crimping electrical connectors as set forth in claim 2wherein said piston means acts to confine the explosive force to effectefficient ignition said explosive device.

10. A tool for crimping electrical connectors as set forth in claim 1wherein said first and second relatively movable die means comprisesfirst and second male dies adapted to independently move toward and awayfrom said relatively fixed die means to crimp a connector therebetween,which includes for positively securing the wire elements to which aconnector is to be crimped in a preselected position relative to saidfemale member, and wherein said piston means acts to confine saidexplosive force to effect efficient ignition of said explosive device.

1. In an electrical-connector-crimping tool for operatively connectingfirst and second wire elements, relatively fixed die means adapted tooperatively support a connector during a crimping operation, first andsecond independently movable die means cooperable with said fixed diemeans to crimp a connector therebetween, piston means for applying anexplosive force to said movable an die means, whereby said movable diemeans will be biased independently toward said connector supported onsaid fixed die means and thereby exert independent compressive forcesagainst said connector to secure said connector to said first and secondwire elements regardless of whether or not said elements are of the samecross-sectional size, and means for detonating an explosive deviceadjacent said piston means for producing said force.
 2. A tool forcrimping electrical connectors as set forth in claim 1 which includesfirst and second reciprocable piston means cooperable with saidrelatively movable die means.
 3. A tool for crimping electricalconnectors as set forth in claim 1 wherein said means for detonating anexplosive device comprises firing pin means and spring means forresiliently biasing said firing pin means toward said explosive device.4. A tool for crimping electrical connectors as set forth in claim 1wherein said relatively fixed die means comprises a female memberadapted to operatively support a conNector, and wherein said first andsecond relatively movable die means comprises first and second male diesadapted to independently move toward and away from said female die tocrimp a connector therebetween.
 5. A tool for crimping electricalconnectors as set forth in claim 4 which includes first and secondspring means for biasing said first and second male dies towarddeactuated positions.
 6. A tool for crimping electrical connectors asset forth in claim 1 which includes spring clip means for positivelysecuring at least one of said wire elements to which a connector is tobe crimped in a preselected position relative to said fixed die means.7. A tool for crimping electrical connectors as set forth in claim 6wherein said spring clip means comprises a pair of opposed spring clipmembers each having portions adapted to positively engage said one wireelement to which a connector is to be crimped, whereby to resistmovement of the element relative to the tool during a crimpingoperation.
 8. A tool for crimping electrical connectors as set forth inclaim 6 wherein said spring clip means includes wire-engaging fingermeans and spring means resiliently urging said finger means toward aposition engaging the wire element to which a connector is to becrimped.
 9. A tool for crimping electrical connectors as set forth inclaim 2 wherein said piston means acts to confine the explosive force toeffect efficient ignition said explosive device.
 10. A tool for crimpingelectrical connectors as set forth in claim 1 wherein said first andsecond relatively movable die means comprises first and second male diesadapted to independently move toward and away from said relatively fixeddie means to crimp a connector therebetween, which includes first andsecond reciprocable piston means cooperable with said relatively movabledie means, which comprises firing pin means and spring means forresiliently biasing said firing pin means toward said explosive device,wherein said relatively fixed die means comprises a female memberadapted to operatively support a connector, which includes spring clipmeans for positively securing the wire elements to which a connector isto be crimped in a preselected position relative to said female member,and wherein said piston means acts to confine said explosive force toeffect efficient ignition of said explosive device.